title: Differences in virulence gene expression between atypical enteropathogenic Escherichia coli strains isolated from diarrheic and healthy ruminants.
abstract: Differences in the pathogenicity of atypical enteropathogenic Escherichia coli (EPEC) strains may be due, at least partially, to different expression patterns of some virulence genes. To investigate this hypothesis, the virulence gene expression patterns of 6 atypical EPEC strains isolated from healthy and diarrheic ruminants were compared using quantitative real-time reverse transcription polymerase chain reaction after growing the bacteria in culture medium alone or after binding it to HeLa epithelial cells. Some virulence genes in strains from diarrheic animals were upregulated relative to their expression in strains from healthy animals. When bacteria were cultured in the presence of HeLa cells, the ehxA and efa1/lifA genes, previously associated with the production of diarrhea, were expressed at higher levels in strains from diarrheic animals than in strains from healthy animals. Thus, the expression levels of some virulence genes may help determine which atypical EPEC strains cause diarrhea in ruminants.
authors.affiliation: Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Horcajo
authors.forename: Gustavo
authors.initials: G
authors.lastname: Domínguez-Bernal
authors.forename: Javier
authors.initials: J
authors.lastname: Carrión
authors.forename: Ricardo
authors.initials: R
authors.lastname: De La Fuente
authors.forename: José A
authors.initials: JA
authors.lastname: Ruiz-Santa-Quiteria
authors.forename: José A
authors.initials: JA
authors.lastname: Orden
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary*; D054308:Enteropathogenic Escherichia coli / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D015511:Goat Diseases / Q000382:microbiology; D006041:Goats; D012329:RNA, Bacterial / Q000378:metabolism; D012756:Sheep; D012757:Sheep Diseases / Q000382:microbiology; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D012329:RNA, Bacterial; D037521:Virulence Factors